# Source code for pymunk.contact_point_set

```__docformat__ = "reStructuredText"

from typing import TYPE_CHECKING, List, Tuple

if TYPE_CHECKING:
from ._chipmunk_cffi import ffi

from .vec2d import Vec2d

[docs]class ContactPoint(object):
"""Contains information about a contact point.

point_a and point_b are the contact position on the surface of each shape.

distance is the penetration distance of the two shapes. Overlapping
means it will be negative. This value is calculated as
dot(point2 - point1), normal) and is ignored when you set the
Arbiter.contact_point_set.
"""

point_a: Vec2d
point_b: Vec2d
distance: float

__slots__ = ("point_a", "point_b", "distance")

[docs]    def __init__(
self,
point_a: Vec2d,
point_b: Vec2d,
distance: float,
) -> None:
assert len(point_a) == 2
assert len(point_b) == 2
self.point_a = point_a
self.point_b = point_b
self.distance = distance

def __repr__(self) -> str:
return "ContactPoint(point_a={}, point_b={}, distance={})".format(
self.point_a, self.point_b, self.distance
)

[docs]class ContactPointSet(object):
"""Contact point sets make getting contact information simpler.

normal is the normal of the collision

points is the array of contact points. Can be at most 2 points.
"""

normal: Vec2d
points: List[ContactPoint]

__slots__ = ("normal", "points")

[docs]    def __init__(self, normal: Vec2d, points: List[ContactPoint]) -> None:
assert len(normal) == 2
self.normal = normal
self.points = points

def __repr__(self) -> str:
return "ContactPointSet(normal={}, points={})".format(self.normal, self.points)

@classmethod
def _from_cp(cls, _points: "ffi.CData") -> "ContactPointSet":
normal = Vec2d(_points.normal.x, _points.normal.y)

points = []
for i in range(_points.count):
_p = _points.points[i]
p = ContactPoint(
Vec2d(_p.pointA.x, _p.pointA.y),
Vec2d(_p.pointB.x, _p.pointB.y),
_p.distance,
)
points.append(p)

return cls(normal, points)
```